Run godot --convert-3to4 (automated conversion)

Apply Godot 4.6 automated conversion: renames Spatial.translate->position,
margin_*->offset_*, tool->@tool, .empty()->.is_empty(), DynamicFont->FontFile,
onready->@onready, export()->@export, and many more.

127 files changed by the tool. Manual fixes still required for:
 - godot_db_manager plugin (incompatible APIs: WindowDialog, Tabs, etc.)
 - lod plugin (Spatial -> Node3D renames)
 - ResourceLoader.load_interactive removed -> load_threaded_request
 - OS.set_window_fullscreen removed -> DisplayServer
 - Viewport.set_size_override removed

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

addons/godot_db_manager/data_label.gd

@@ -1,10 +1,10 @@
+@tool
 """
 class GDDBDataLabel
 """
 
 class_name GDDBDataLabel
 
-tool
 extends Label
 
 signal resize_property
@@ -27,7 +27,7 @@ func _input(event : InputEvent) -> void :
 	var evLocal = $resize_ctrl.make_input_local(event)
 
 	if event is InputEventMouseButton :
-		if(event.button_index == BUTTON_LEFT):
+		if(event.button_index == MOUSE_BUTTON_LEFT):
 			if(event.pressed):
 				var rect = Rect2(Vector2(0, 0), $resize_ctrl.get_size())
 				var inside = rect.has_point(evLocal.position)